You think wrong. The reason is three fold. One, we're broke and sick of war as a nation. Two, Republicans only care about getting involved in foreign conflicts if someone is shooting at Americans or are threatening our assets and top allies. They don't care about non-American struggles for independence, unless a victory would screw over a power that we're afraid of.
And three, they just plain hate Obama and will nay say even the things they agree might be good. With elections in the US now only a little more than a year away, virtually all legislation is being viewed in terms of how it will enhance or hurt the parties chances of winning the White House. Any measure of approval Republicans give Obama makes them look weak to their base, and looks like a + mark on Obama's "What I did with my 4 years in the White House" scoreboard.
Obama didn't seek Congressional approval because he knows that both Republicans and Democrats would have rejected it. The irony is all this BS is on par with the level of warfare we've waged previously without a lick of congressional approval. Unlike previous administrations, Obama was committed to acting publicly when acting covertly may have been far more prudent. People will disagree about his motives for that. His supporters will say he's fulfilling our commitment to supporting fledgling democratic movements with something other than black ops and weapons. His detractors will claim it's just a PR move and/or stupid and reckless.